FOP - Exception <java.lang.IllegalArgumentException: URI is not hierarchical>java.lang.IllegalArgumentException: URI is not hierarchical

Hello,

4 years ago I wrote a book. Now it is time to update it.
So I changed the asciidoc sources, did not change the build setup, but 
now fop borks. Any hint would be highly appreciated.
My command and error message is:


$ fop  -d -v -c ./dyslexicfontconfig.xml  ./lpi_essentials.fo 
./lpi_essentials-di.fo
FOP Version 2.1
[ERROR] FOP - Exception <java.lang.IllegalArgumentException: URI is not 
hierarchical>java.lang.IllegalArgumentException: URI is not hierarchical
	at java.io.File.<init>(File.java:392)
	at org.apache.fop.fonts.FontCache.addFont(FontCache.java:335)
	at 
org.apache.fop.fonts.DefaultFontConfigurator.getFontInfo(DefaultFontConfigurator.java:173)
	at 
org.apache.fop.fonts.DefaultFontConfigurator.addFonts(DefaultFontConfigurator.java:136)
	at 
org.apache.fop.fonts.DefaultFontConfigurator.configure(DefaultFontConfigurator.java:89)
	at 
org.apache.fop.render.PrintRendererConfigurator.getCustomFontCollection(PrintRendererConfigurator.java:147)
	at 
org.apache.fop.render.PrintRendererConfigurator.setupFontInfo(PrintRendererConfigurator.java:127)
	at org.apache.fop.render.intermediate.IFUtil.setupFonts(IFUtil.java:170)
	at 
org.apache.fop.render.intermediate.IFRenderer.setupFontInfo(IFRenderer.java:187)
	at org.apache.fop.area.RenderPagesModel.<init>(RenderPagesModel.java:75)
	at org.apache.fop.area.AreaTreeHandler.setupModel(AreaTreeHandler.java:135)
	at org.apache.fop.area.AreaTreeHandler.<init>(AreaTreeHandler.java:105)
	at 
org.apache.fop.render.RendererFactory.createFOEventHandler(RendererFactory.java:350)
	at org.apache.fop.fo.FOTreeBuilder.<init>(FOTreeBuilder.java:107)
	at org.apache.fop.apps.Fop.createDefaultHandler(Fop.java:104)
	at org.apache.fop.apps.Fop.<init>(Fop.java:78)
	at org.apache.fop.apps.FOUserAgent.newFop(FOUserAgent.java:182)
	at org.apache.fop.cli.InputHandler.renderTo(InputHandler.java:107)
	at org.apache.fop.cli.Main.startFOP(Main.java:186)
	at org.apache.fop.cli.Main.main(Main.java:217)



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Jeroen Baten              | EMAIL :  [email protected]
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